1. Field of the Invention
This invention relates to aluminum alloy sheet materials having not only high strength but also excellent formability.
2. Prior Art
Conventionally, various aluminum alloy sheet materials have been proposed for use as automobile body panels, which include, for example, an aluminum alloy sheet material containing 3.5 to 5% by weight Mg as proposed by Japanese Provisional Patent Publication (Kokai) No. 3-111532, and an aluminum alloy sheet material AA-X5085 containing 5.8 to 6.8% by weight Mg.
With the recent diversification of automobile body configuration, it is required that aluminum alloy sheet materials for use as automobile panels have not only high strength but also excellent formability. However, conventional aluminum alloy sheet materials having high strength are poor in formability, whereas ones having excellent formability are unsatisfactory in strength.